In recently years, plastic insulating materials are expected as film materials for film capacitors for communication, electronic devices, electric power, medium and low voltage phase advancement and inverter, piezoelectric devices, pyroelectric devices and dielectric materials for transfer printing carrier since they have a high insulation resistance, excellent frequency characteristics and excellent flexibility.
A film capacitor is usually comprised of a film structure comprising a dielectric resin film subjected to aluminum or zinc deposition on its surface, or a film structure comprising multi-layers of aluminum foils and dielectric resin films, and recently there are used a lot of capacitors comprising a dielectric resin film and an electrode formed thereon by metal deposition.
A highly dielectric film for a film capacitor is usually formed in the form of single layer comprising a dielectric resin as a film forming resin, and generally non-fluorine-containing thermoplastic resins such as polyester and polyphenylene sulfide (PPS) and fluorine-containing resins such as vinylidene fluoride (VdF) having high dielectric constant are studied as a film forming resin.
However, since there is a limit in the use of only a resin which is an organic compound for recent demand for high energy density and blending of highly dielectric inorganic particles is carried out (Patent Documents 1 to 4).